Refrigerating system



Dec. 6, 1932. s. HILGER REFRIGERATING SYSTEM Filed Nov. 16. 1929Patented Dec. 6, `1932 UNITED STATES enonen nILGEn, or cIIIcAeo,ILLINOIS mnrem'rme s'Ys'rEIr Application led November 16, 1929. SerialNo. 407,583.

The present invention relates to improvements in refrigerating systems,and has particular reference to systems of the type disclosed in mycopending application, Serial No. 306,563, il'ed September 17, 1928.

The primary objects of the invention reside in the provision of-a newand improved refrigerating system havin a plurality of refrigeratingunits preferaly a substantially vertical stand, .inwhich the liquid headis substantially eliminated, which can operate on relatively lowpressures and low pressure dilerences, in which there is but a slighttemperature di'erence between the units, said .units havingsubstantially the same evaporating effect, and in which an exact controlis unnecessary. v

A more specific object resides in the provision of a novel refrigei'atinsystem of the foregoing character inwhic the refrigerant is carried fromeach unit to the next by an injector action.

Another object resides in the provision of a new and improvedrefrigerator system which comprises a plurality of superimposed unitsrigidly connected in a unitary header, and in which each unit comprisesa. liquid chamber, and aV circulating element opening therefrom anddisposed entirely 3 Itherebelow so as to be iiooded constantly.

A further object of the invention is to provide a novel refrigeratingsystem comprising a plurality of superimposed liquid chambers and aplurality of circulating ele- 5 ments for circulating liquid from saidcham- 'bers through the space to be cooled, in which means is providedfor automatically discharging gas and entrained liquid upwardly from onechamber to another, and in which o each element discharges to thetop ofthe chamber below the chamber from which it receives liquid, thuseecting a recirculation of the refrigerant. l

Other general objects reside in the provision of a novel refrigerator ofthe foregoing characterin which oil in the refrigerant is separated'outin the first or lowermost unit,

in which the liquid is automatically and uniformly distributed frombottom to top upon starting up from an idle condition, in which aarranged in` claims.

quick heat transfer is effected, and in which the refrigerant issuperheated inthe uppermost unit before withdrawal.

Further objects and advantages will become apparent as the descriptionproceeds. In the accompanying drawing, Figure 1 is a side elevationalview of -a refrigerating system embodying the features of my invention.Fig. 2 is an axial sectional view of the header-taken along line 2-2 ofFig. 3.'

Fig. 3 is` an axial sectional view of the header taken along the line3-f-3 of Fig. 1.

Fig. 4 is a transverse ysectional view taken along line 4 4 of Fig. 2.

Fig. 5 is a transverse sectional view taken 65 along line 5-5 of Fig. 2.

While the invention is susceptible of various modifications andalternative constructions, I have shown in the drawin and will hereindescribe in detail the pre erred embodiment, but it is to be understoodthat I do not thereby intend to limit the invention to' the speciiicformdisclosed, but intend to cover all modifications and alternativeconstructions falling within the spirit and scope of the invention asexpressed in the appended Referring more particularly to the drawing,the refrigerating system constituting the exemplary embodiment of theinventioncomprises a plurality of superimposed refri erating units,preferably arranged in a su stantially vertical stand.

In the present instance, six units are provided, and these unitscomprise respectivel 'g5 six superimposed chambers 10 to 15. Pre erably,the chambers are formed in an integral cylindricalheader. To this end,an elongated cylindrical casing 16 closed at the bottom and top by endwalls 17 and 18 respec- 90 tively is provided. Interposed in the casing16 in parallel spaced relation along its length are a plurality oftransverse partition walls 19 to 23 which together with the end walls 17and 18 serve to define the end walls of the 95 chambers 10 to 15.

The lowermost chamber 10 is the refrigerant inlet or supply chamber, thetop chamber 15 is the superheated refrigerant gas takev off Chamber, andthe intermediate chambers 11 to 14 are conveniently designated asliquidrefrigerant distribution chambers.

Suitable means isv provided for supplying refrigerant from an externalsource of supply (not shown) to the chamber 10. In the present instance,this means comprises an inlet pipe 24 opening substantially tothe top ofthe chamber 10. The refrigerant usually is available from -the source ata relatively high pressure, and is supplied through suitable pressurereducing means (not shown) and supply control lmeans (not shown) to thechamber 10 at a relatively low pressure. At the reduced inlet pressure,the-v refrigerant is at or near the boiling temperature. Some heat willbe abstracted thereby from the gas refrigerant discharged to the chamber10 from the lowermost circulating element as will be hereinafterdescribed. Hence, the refrigerant will be present in the chamber 10 inboth vapor and liquid phases, but the amount of liquid available will besubstantially in excess of the evaporation requirements.

The liquid refrigerant will collect in the bottom of the chamber 10, andthe vapor will collect in the top. Any oil present in the refrigerantwill settle to the very bottom from where it can be withdrawn through asuitable oil drain 25. The chamber 10 thus can also be appropriatelydesignated asl the oil separation chamber. l

Means is provided for conveying refrig erant from the chamber 10upwardly successively to each of the other chambers. In the instance ofchambers 10 and 11, this means comprises an open ended tube 26 mountedvertically in the partition wall 19. Of the tube 26, the lower endterminates near the top of the chamber 10 but preferably downwardly andslightly below the inlet 24 and the upper or discharge end terminatesnear the top of the chamber 11 and constitutes' thev yrefrigerant inletmeans corresponding to the inlet 24 for the chamber 10. Preferably, thelower end of the tube 26 is slotted longitudiy nally as indicated at 27.

-into the chamber 11 also is in excess of the evaporation requirement ofthat unit, and hence the liquid level will risetherein as in chamber 10.

' Similar tubes26 are provided for conveying gaseous and liquidrefrigerant upwardly '14. The tubes are staggered laterally to perfromone to the other ofthe chambers 11 to lowermost chambers.

The chamber 14 communicates with the chamber 15 through suitablerefrigerant superheating elements as will be hereinafter described. Thegaseous refrigerant is withdrawn from the top of the chamber 15 througha suitable discharge pipe 28 leading to a compressor `(not shown). It

will be understood that the amount of refrigerant which should besupplied tothe chamber 10 is ydetermined by the evaporating requirementsof the system, and that the supply may be controlled manually orautomatically in accordance with the temperature of the gas leaving thechamber 15.

Suitable means is provided for circulating liquid refrigerant from eachof chambers 11 to 14 through the space to be cooled. While this meansmay take various forms, preferably'a plurality of suitable circulatingcoils are provided. I have shown a single coil for each of chambers 11to 14, but it is to be understood that any desired number of coils inparallel may be provided. Thus, four coils 29 to 32 are connectedrespectively to receive liquid refrigerant from the chambers 11 to 14-Each of the coils 2,9 to 32 is disposed entirely below the chamber fromwhich it receives liquid refrigerant. Thus, the coil 29 is connected atits lower and inlet end to a pipe fitting 33 which extends through theside of the casing 16 near the lower end of the chamber 10 and thenupwardly through the partition wall 19 to the bottom of the chamber 11,and is connected at its upper anddischarge end to a pipe fitting 34which opens through the casing to the top of the chamber 10. Similarfittings 33 and 34 are provided for connecting the coils 30 to 32 to theproper chambers. Since each circulating coil is disposed entirely belowvthe chamber from which it draws its supply of refrigerant, the liquidin the chamber constitutes a substantial head at all times tending tomaintain the coil in floodedl condition and to increase the rate ofcirculation.

` As a result, any bubbles of gas tending to collect on the innersurface of the coil are rubbed ofl thereby keeping the surface wetted,and'in general a quick rate of heat transfer is obtained. Due to thesubstantial head forcing circulation in one direction, danger ofbackfire and of entrapment of liquid by the sudden formation of gas iseliminated.

The refrigerant that is evaporated in the coils is`returned to thechamber below that from which the'L liquid is\11eceived, and joins withthe vapor passing to the\chamber im- -ing liquid refrigerant from theChamber 14 into the chamber 15 is provided, and but a relatively smallhead ofliquid is maintainedA in the chamber 14. Opening from the lowerend of the chamber`14 at a point somewhat below the discharge end of thetube 26 is a pipe fitting 35 to which is attached the lower and inletend of an evaporating and superheating coil 36 generally similar in formto the coils Q9 to 32.

'1 he upper and discharge end of the coil 36 is connected to a pipefitting 37 which extends through the casing 16 into the upper part ofthe chamber 14 and then upwardly through the wall 23 to the floor of thechamber 15. If the liquid level in the chamber 14 rises above the mouthof the fitting 35, the liquid will partly fill the. lower leg ofthe C01136and will evaporate therein, and the resultant gas together with othergas from the chamber 14 will pass therethrough to the chamber 15.

A fitting 38 opening vertically from the top of the chamber 14 throughthe wall 23 and then laterally through thecasing 16 is connected to thelower inlet end of a second superheating coil 39. The upper dischargeend of this coil is connected to atting 40 opening through the casing 16to the top of the chamber 15. Thus, any gaseous refrigerant passing fromthe chamber 14 to the chamber 15 is superheated before being dischargedinto the latter. The superheated gas is removed from the chamber 15 tothe source.

Preferably, a restricted port 41 is formed in the lower bend of eacli ofthe ttings 33 within the casing 16. The ports 41 permit any oil thatmight be carried from the chamber 10 over into the chambers 11. to 14 todrip back, and also serve to permit all the liquid refrigerant in thesystem to return to the bottom of the header when the system is at rest.

I claim as my invention 1. A refrigerating system comprising, in

combination, a unitl having aspace adapted to contain separated liquidand vapor phases of the refrigerant, an inlet line for supplyingrefrigerant'under pressure to said space, an oil drain opening from thebottom of said space, and an outlet line having its inlet disposed atthe predetermined normal level of the liquid for discharging vapor orvapor and entrained liquid from said space to a pressure lower than theinlet pressure.

2. A refrigerating system comprising, in combination, a unit having aspace adapted to contain separated liquid and vapor phases of therefrigerant, an inlet line for supplying refrigerant under pressure tothe top of said space, an oil drain opening from the bottom of saidspace, and an outlet line having its inlet disposed at the predeterminednormal level of the liquid and below the discharge end.

of said inlet line for discharging vapor or vapor and entrain'ed liquidfrom said space to a pressure lower than the inlet pressure.

3.A refrigerating system comprising, in combination, two superimposedchambers adapted to contain separated liquid and vapor phases of therefrigerant, inlet means for supplying refrigerant under pressure to theupper portion of the lowermost chamber, al vertical injector tubeopening from the lower chamber at an intermediate point below said inletmeans to the upper portion of the uppermost chamber, dischargemeansopening from the upper portion of said upper most chamber, and a liquidcooling coil opening from the bottom of said uppermost chamber anddischarging to thetop of said lowermost chamber.

4. A refrigerating 'systemy comprising, in combination, an'elongatedvertical casing, a plurality of vertically spaced partition walls insaid casing dividing the latter into a plurality of verticallyspacedliquid refrigerant distributing chambers, means for supplying liquidrefrigerant to the upper end ofthe lowermost chamber, means forwithdrawing refrigerant gas from the upper end of the uppermost chamber,a plurality of connecting pipes extending respectively through saidwalls, one from adjacent the upper end of each chamber lto adjacent theupper end of the chamber immediately above and to above the inlet endofthe pipe immediately aboye, and a plurality of liquidcirculatingcoils, one for each chamber excepting the lower- `mostchamber, each coil opening from the bottom of one of said last mentionedchambers and discharging to the chamber immediaftely below.

5. A refrigerating system comprising, in combination, a pair of unitsdefining two superimposed chambers each adapted to contain separated liuid and vapor phases of the refrigerant, an injector pipe opening froman intermediate point in the lower chamber to an intermediate point inthe upper chamber, and liquid circulating means opening from the lowerportion of the upper chamber to the upper portion of the lower chainber.

6. A refrigerating system-comprising, in combination, a pair of unitsdefining two superimposed chambers each adapted to contain separatedliquid andyapor phases of the refrigerant, an injector pipe opening froman intermediate point in the lower chamber to an intermediate point inthe upper chamber, and liquid circulating means opening from the lowerportion of the upper chamber to the upper portion of the lower chamber,said means being located entirely below the upper chamber.

of a lower pressure in said upper chamber than in said loweri chambertoI convey automatically liquid and gaseous refr1gerant from the latterto the former, and cooling means disposed entirely below said upperchamber for circulating liquid therefrom and discharging to said lowerchamber.

8. A refrigerating system comprising, in combination, a chamber adaptedto contain liquid and vapor phases ofthe refrigerant, means forsupplying refrigerant under pressure to said chamber, means for removingvapor from the top of said chamber to a lower pressure, 'the inlet ofsaid last-men. tioned means opening at an intermediate oint in said.chamber, and a liquid circuating coil opening from the normal liquidspace of said chamber, said coildischarging to said first mentionedmeans. f

9. A `refrigerating system comprising, in combination, a cylindricalcasing, transverse partitions in said casing defining two superimposedchambers, means for supplying refrigerant to the lower chamber, aninjector pipe opening through the intermediate partition from anintermediate point in the lower chamber to anintermediate point in theupper chamber, a liquid circulating coil opening from the bottom of theupper chamber through said intermediate partition, then downwardly intothe lower chamber, then laterally out of the lower chamber and thenthrough the space to be cooled, and discharging to the top of the lowerchamber, and means. discharging from the top of the upper chamber.

10. A refrigerating system comprising, in

combination, a vertical stand of superimposed chambers, means forsupplying liquid refrigerant to the lowermost chamber, in# jector meansfor conveying vapor or a mixture of vapor and entrained liquid upwardlyfrom each chamber to the next chamber, meansfor circulating liquid fromeach of the chambers above the lowermost chamber through a tortuous pathand then discharging to a lower chamber, and means for withgrawingrefrigerant from the upper cham- 11. A refri'gerating system comprising,in

combination, a vertical cylindrical casing, a

` plurality of transverse partitions in said 'casing defining a bottomchamber, a top a chamber and a plurality of intermediate dischargedtherefrom, a plurality of liquid A chambers, means for supplying liquidre1- frigerant to the top of said bottom chamber,

injector means for conveying vapor or 'vapor and entrained liquid fromeach chamber upwardly to the next chamber, said injector means in eachinstance terminating at an intermediat'e point in the chamber to whichit discharges so as to permit a separation of the liquid and vaporphases of the refrigerant circulating coils, one for each chamber aboveentirely below its chamber and opening from the bottom thereof anddischarging to the chamber-immediately below, gas circulating means`opening from the top chamber, and means for withdrawing gas from saidlast mentioned means.

l2. A refrigerating system comprising, in combination, threesuperimposed chambers, means for supplying refrigerant in liquid andvapor form to the lowermost chamber, means forinjecting liquid entrainedvapor from the lowermost chambernto the intermediate chamber atanintermediate point, means for circulating liquid from the bottom of saidintermediate chamber. and discharging to the top of said lowermostchamber, a superheating coil opening from said intermediate chamber at apoint below the 'discharge end of said injector means and discharging tothe bottom of the uppermost chamber, a second superheating coil openingfrom the top of said intermediate chamber and discharging to the upperportion of said uppermost chamber, and; means for withdrawing thegaseous refrigerant from the uppermost chamber.

13. A refrigerating system comprising, .in combination, a refrigeratingunit having a space adapted to contain separated liquid and vapor phasesof the refrigerant, aninletl line for supplying refrigerant underpressure to said space, an outlet liquid and vapor line having its inletendvopening at the normal level of the liquid in s aid space, means formaintaining a lower pressure in said outlet line than in said inletline, and liquid circulating means opening from said space at a pointbelow the normal level of the liquid, said means being disposed belowsaid unit.'

In testimony whereof, I have hereunto afflxed my signature. Y

GEORGE HILGER.

the bottom chamber, ea ch coil being located

